Concrete-form clamp



ct. v30 E923. 1,472,436

E. R. PERRY CONCRETE FORM CLAMP Filed Dec. 29. 1922 his@ Patented @et 30, 1923.

EARL R. PERRY, F WORCESTER, MASSACHUSETTS.

i CONCRETE-FORM CLAMP.

Application led December 29, 1922. Serial No. 609,681.

To all whomy t may concern.'

Be it known that I, EARL R. PERRY, a citii zen of the United States. residing at Worcester. in the county of Worcester and State of lvlassachusetts, have invented anew and use- 't'ul Concrete-Form Clamp, ot which the tol# lowing is specification.

This invention relates to a clamp for tightening up and holding forms for the molding of concrete. It is capable of being used :tor forms of any desired kind and Vcharacter and as a clamp `:for general purposes. v

The principal objects of the invention are to provide a clamping device for one end ot a rod of such a nature that it will consist of two parts only that are duplicates and can be made in the same mold if formed et' cast metal; to avoid the use of screw threads or other finished parts and provide a construction which will work quickly and will. require a minimum manipulation and will hold the rod firmly in any position to which it may be brought by the clampinn' device.

Reference is to be had to the accompanyinnV drawings. in which Fig. l is a horizontal sectional view of a part of a concrete mold showing a preferred form of this invention applied thereto:

Fig. 2 is a side elevation of the same;

Fig. 3 is a full size view of one of the parts of the clamp; and

Fig. 4 is an end view of the same.

The invention is shown as applied to a rod 10 which may have a head or nut on one end and is to be tightened up at the other end bv this device. The clamping device consists of two collars 11 madefalike in all respects. reversed. and placed end to end on theV rod. One end of the rod being arranged in any desired way so that it cannot pull through the mold. vthe other end is drawn up by my improved clamp. Each part of this collar 11 comprises a main body which has on thevend a cam surface 12 sloping lafradually and uniformly throughout a complete circle with an abrupt drop or termination at 13. Near the other endv this member is provided with a square, hex, or other shape 14 on which a. wrench can be applied for operating the device. It is also provided with a passage 15 therethrough, this passage being' semi-circular at both ends and having the two semi-circles connected by diverging` walls so that it is of a general triangular shape. The object of thisshape is to secure al wedding action and to permit of the device being used on rods `10 of diii'erent sizes. For clamping the collar in place on the rod a set screw 17 or the like is used.

It will be understood that two of these clamps are placed on the rod end to end reversed with the two cam` surfaces 12 in contact, as shown at the right in Fig. 2. Although only one set of these clamps would be used on a single rod. I have shown two of them in this figure to illustrate the clamping action. The one at the left shows the device in its clamping position, while the one at the right shows it in its original position and of course two of them could be used in that way instead of an ordinary nut or head on the end of the rod.

In using the device. the clamping head that is nearest the frame or wall of the form is located on it by tightening' its set screw 1.7 lightly with the nnfers. Then the other collar is set up close to it. as shown at'the right in 2 and its set screw 1.7 tightened up tight with a wrench. The first set screw can then be loosened if too tifrht but ordinarily being: tightened bv the fingers it can be left that wav. lt is merely tinhtened to prevent rotation on the rod. Then the operator places a wrench on the hex at 14 nearest the form and turns it to torce the cams apart. This pulls the rod throufrh the inner collar and forces the other collar outwardly away from the form. The set screw in the collar nearest the form is then tightened up tight with a. wrench and the outer collar removed.

This constitutes a powerful clamp for this purpose and provides for the construction of the complete clamp by the use of only one mold. the two parts of the clamp being duplicates. It eliminates the ordinary screw threaded arrangements. cams. and levers and the like which are commonly used. It provides tor the use ot' a single size of clamping head with three or more sizes of wire rods and saves a great deal of time in the clamping of the forms as well as in the manufacture of the device.

Although I have illustrated and described only a single form oi the invention, l am aware of the fact that modifications can be made therein by any person skilled in the art without departing 'from the scope of the clamp comprising two identical Collarsl adapted to be received lon a rod to be held,

saidrcollars being arranged right and left. handed on the rod and having (3o-acting adjacent "cam surfaces on their ends, the

cellar lwhich is nearest the vform, loetvveeny that andthe outer one7 being adapted tol be turnedvon the rod to force the outer` `collar outvvardly'and hold the rod firmly.

2. As an article of manufacture, a collarV or clamping the rod` of a concrete mold shaped end vand the otherend of' polygonal Vform andhavingfra passage therethrough 'from one lend tovtlie'otherfor the rod, and

means for clamping it to? the ro'd. Y Y

3. As an article of manufacture, a collar for clamping aV rodhaving a. longitudinal passage therethrough larger'at one side than at the other sideyand means for clamping the collar to the rod, sa-id collar. having a cam-shaped end for the purpose described.

InV testimony whereof l? have hereunto affixed my signature. Y Y Y Y Y EARL R. PERRY.

"iirni consistingV of .a device having a oam- Y 

